Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In

Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In



The Case for High-Intensity Training for Older Runners

In order to reduce the decline in aerobic capacity with advancing age, training must be intense.

Adapted from Fast After 50: How to Race Strong for the Rest of Your Life with permission of VeloPress. Preview Joe Friel’s book at

Research tells us that the performance decline we typically experience with aging has a lot to do with how active we are while growing older. For example, a paper released in 2000 examined the combined effects of age and activity level over time. The researchers reviewed 242 studies comparing aging and VO2max involving 13,828 male subjects. Each of the subjects was assigned to one of three groups based on how active they were: sedentary, moderately active exerciser, or endurance-trained runner.

Aerobic capacity was highest in the runners and lowest in the sedentary group. No surprises there. The aerobic capacity changes per decade of life were: sedentary, 8.7 percent; active, 7.3 percent; runners, 6.8 percent. What this means is if at age 30 a man had a VO2max of 60 and then for the next 30 years didn’t exercise and lived a “normal” (sedentary) life, he could expect his aerobic capacity at age 60 to be around 46. If he was moderately active, it would be about 48. And if he trained as an endurance runner, it would be in the neighborhood of 49. Those are not significant numeric changes. But for normal folks who generally see VO2max declines of 10 percent and greater for a 10-year period, these numbers are really high.

But regardless of the actual size of the change, here’s the main message: The study further reported that the subjects who were endurance-trained runners significantly decreased their volume (miles run per week) and training intensity as they got older. That’s a common practice with aging athletes. So maybe it’s not simply working out that maintains aerobic capacity and therefore, in part, race performances; instead, it is how much training you do and how intensely you do it.

RELATED: Fast After 40: Master Your Stride

In 1987, Dr. Michael Pollock and his colleagues at the Mt. Sinai Medical Center in Milwaukee, Wisconsin, reported a watershed finding in the understanding of performance and age. Dr. Pollack reported an astonishing finding that lent further credibility to the idea that very strenuous exercise was an aerobic capacity preserver. Well-trained, competitive endurance runners with an average initial age of 52 were able to totally maintain VO2max values over a 10-year period.

In the full group of 24 athletes, VO2max went into a tailspin, with an average 9 percent decline during the 10 years of the study. However, Pollock discovered that 11 of the 24 had continued to train vigorously and were still competitive a decade after the initial testing. When he categorized the results, he found that the more active athletes had absolutely maintained their average VO2max at a steady 53 ml/kg/min (10 years earlier it had been 54) despite being now in their early 60s. The less active subjects had seen their VO2max values plummet by 12 percent. In Pollock’s paper, “more active” meant that athletes continued to do high-intensity workouts while maintaining their volume.

Just like Pollock’s study, other research on aging in experienced endurance athletes generally supports the notion that in order to reduce the decline in aerobic capacity with advancing age, training must be intense.

That typically means training anaerobically—at or above the lactate threshold. For experienced endurance athletes, an exercise regimen based solely on long, slow distance (LSD) will do little to improve or even maintain your aerobic fitness status over the years.

If high-intensity training is something you haven’t done for a long time or have never done, you must consider several things: the type of hard workouts, the frequency of hard workouts, your short-term recovery from hard workouts, and your nutrition relative to hard workouts. Let’s look at high-intensity training designed with one critical goal: aerobic capacity.

Guidelines for High-Intensity Training

The most effective and efficient use of your time and energy to increase training intensity is to do some type of interval training.

Important point: When you perform intervals, the absolute intensity, the duration of the repetitions, the number of repetitions, and the duration of recovery between intervals must be only slightly more challenging than your estimated current capacity for physical stress.

What that means is that you must know or be able to sense your physical limits and not exceed them. It’s best to take a conservative approach to intervals if it’s been a while since you last did such a workout. Don’t try to get in shape in just a handful of these sessions. Too much, too soon will nearly always result in a breakdown of some sort, such as injury. Take a long-term approach—as in several weeks—to safely produce the results you want.

Because an interval session can be quite stressful, it should be preceded by a gradually progressive warm-up. This approach has also been shown to improve workout performance. Stop the workout when a reasonable workout goal is attained, when it is apparent that high-end performance is declining, or when the effort feels unusually high for the output (pace, speed, power). My advice to the athletes I’ve coached for the past 30-some years has always been the same: Stop when you know you can do only one more interval. The last interval is the one to be most wary of, so simply don’t do it.

RELATED: Fast After 40: Master Your Strength Training

Note that I am not going to describe specific interval workouts for each individual endurance sport. I am going to assume that as a lifelong athlete, you are familiar with interval training and that you either have a record of or remember the interval workouts for your sport that have worked for you in the past. If this is not the case, you will need to research the proper interval training for your sport.

I am also not going to prescribe specific methodology for measuring intensity. Again, I am going to assume that your years in your sport have given you a strong foundation in monitoring the intensity of your workouts. You can use a rating of perceived exertion (RPE), heart rate, lactate threshold heart rate, or functional threshold power if you are using a power meter and are familiar with that measurement. Go with whatever you are comfortable using and whatever is most repeatable for you.

I recommend that you keep track of your heart rate even if you do not use it to measure intensity. Heart rate is a useful component in determining the state of your fitness and the rate at which you are improving it, as you will see below.

If you have been diagnosed with coronary heart disease, have concerns about your heart health, or are taking statins or other medications that alter heart rate, then you should consult your doctor before starting an interval training program. Fortunately, the risk of heart attack among otherwise apparently healthy athletes as they age is quite low.

If you’ve previously done intervals throughout your sport career but have had a gap in recent years, then you know how to get started again. Just be conservative (as I mentioned before) with the progression of this workout. If LSD training has been your only training method, you may need some guidelines for getting started with interval training. Here is what I suggest for the first few sessions for someone who has not done interval training recently.

Step 1. Warm up 10–30 minutes gradually, ratcheting intensity up to a moderate effort. It’s common for older athletes to need more warm-up time than young athletes. Warm-up may also vary by sport. For example, it is typically longer for cycling than for running. Swimming generally falls between these two.

Step 2. Do 3 × 3-minute intervals with each interval at or slightly below lactate (anaerobic) threshold and 1 minute of light recovery between them. As I mentioned before, the gauge of intensity for an interval workout such as this may be based on heart rate, pace, speed, power, or perceived exertion. Some of these measurements are better than others, depending on the sport. Heart rate–based intensity is perhaps the worst way to gauge how hard to work with intervals, especially short ones of a few minutes or less, as heart rate rises slowly during each interval. It may take several minutes to achieve lactate threshold, during which time you are left guessing how hard to work. Most athletes err on the side of starting intervals too fast to force heart rate up quickly, and then they slow down later as the goal heart rate is finally achieved. This is just the opposite of what should be done; instead, you want to finish each interval with a slightly higher intensity than when you started.

Step 3. Cool down with several minutes of easy exercise. As with the warmup, the duration of the cooldown depends on the sport, with cycling typically long and running relatively short.

RELATED: Fast After 40: Master Your Injury Prevention

At first you should most likely do only one such interval workout in a seven-day period. Over time, however, you can increase the number of weekly sessions to two if you have the stamina and time. It’s not common for senior athletes to be capable of doing more than two of these in a week. I’ve coached some who could, but they are rare and more likely in their 50s than their 70s.

* * * *

Joe Friel’s groundbreaking new book Fast After 50 is for every endurance athlete who wants to stay fast for years to come. For runners, cyclists, triathletes, swimmers, and cross-country skiers, getting older doesn’t have to mean getting slower. Drawing from the most current research on aging and sports performance, Joe Friel—America’s leading endurance sports coach—shows how athletes can race strong and stay healthy well past age 50. In Fast After 50, Friel offers a smart approach for athletes to ward off the effects of age. Friel shows athletes how to extend their racing careers for decades—and race to win.